StoreKit 2 Saved Transaction Identifiers

What information needs to be saved via UserDefaults as the result of a IAP transaction with a single non-consumable product? In the StoreKit 2 SKDemo it appears only consumable product purchases are saved via UserDefaults. It seems like for a non-consumable purchase I should be saving the purchaseDate, and the originalID or id.

What about saving the transaction.productID? Is this a unique identifier for every transaction?

StoreKit 2 Saved Transaction Identifiers
 
 
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